I have built several like this. There are two major brands to consider. Sanwa and Seimitsu. Sanwa and Seimitsu buttons are essentially the same, just different colors and the Seimitsus are available with proper microswiches if you want them, or threaded fastening instead of panel-pop-in tabs.
As for joysticks, it depends on what kind of a gamer you are. Semitsu's flagship joystick is the LS-32, and it's got a very tight deadzone with nice deep corners and a very small throw. Tighter spring though.
Sanwa sticks, on the other hand, have less-deep corners, a lighter spring, and a little more throw. There is a slightly larger deadzone in the middle. Also, Sanwa sticks have less depth below the panel, and are preferred for the "extra-thin" joystick designs.
You can get either with balltops or bat tops, in a variety of colors, and with a plastic shaft cover or just bare stainless steel.
I would suggest the Seimitsus for shooter fans, since they have a very tight feel and little to no deadzone for that twitch-sensetive movement. Sanwas are prefered for fighting games because the slightly larger deadzone, softer throw, and more rounded gate are ideal for all those rotation combos, and the slightly larger deadzone helps to avoid accidentally hitting a corner you don't want to when pulling off harder combos like dragon-punch or half/full circle rotations.